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....and what does PM stand for as far as contacting the right person to make the purchase of the harness. its for an '08 535i. im looking to replace the door speakers with (4" polk), tweeters (polk), under seat subs (sws-8), rear deck (4" polk), and add 2 L7 10" sub, use one 5 channel alpine amp and a hifonics brutus 1300 watt rms amp

....and what does PM stand for as far as contacting the right person to make the purchase of the harness. its for an '08 535i. im looking to replace the door speakers with (4" polk), tweeters (polk), under seat subs (sws-8), rear deck (4" polk), and add 2 L7 10" sub, use one 5 channel alpine amp and a hifonics brutus 1300 watt rms amp

Private Message...

For the 5-Series, a two harness kit (one for the iDrive unit and one for the OEM amp in the trunk) is needed if all the 6-channels are going to be powered by aftermarket amps.

Technic or anyone else out there that can help me.
I have this harness from Technic and it is very high quality(thanks man) I installed it yesterday and linked it all up with my Boss PH4.400 Phantom amp but now have the annoying alternator whine. I guess this is caused from bad earthing.

Technic or anyone else out there that can help me.
I have this harness from Technic and it is very high quality(thanks man) I installed it yesterday and linked it all up with my Boss PH4.400 Phantom amp but now have the annoying alternator whine. I guess this is caused from bad earthing.

So my question is where is the best place to earth on my E60 '2005'??

Thanks Guys

In the 3-Series there is a ground point close to the OEM amp, try to find one close to where the E60 has its OEM amp.

If there's none then ground it directly to the OEM battery. All audio grounds should converged there.